Ratchet-drill brace



(No Model.)

W. P. NOLAN. RATGHET DRILL BRAGE.

No. 484,231. Patented Oct. 11, 1892.

WITNESSES: V I .I/Vl/E/VTOH v S S I v 1 r ATTORNEYS UM -ran STATES I PATENT .Fme,

WILLIAM P. NOLAN, OF SAN FRANCISCO, CALIFORNIA.

RATCHET-DRILL BRACE.

SPECIFICATION forming part of Letters Patent No. 484,231, dated October 11, 1892 v Application filed November 3, 1891. derial No. 410,746. (No model.)

To all whom it may concern:

Be it known that I, WILLIAM P. NOLAN, of San Francisco,in the county of San Francisco and State of California, have invented a new and Improved Ratchet-Drill Brace, of which the following is afull, clear, and exact description.

The object of the invention is to provide a new and improved ratchet-drill brace which is simple and durable in construction, very effective in operation, and arranged to revolve the drilling-tool at a high rate of speed in either direction.

Theinvention consists of certain parts and details and combinations of the same, as will be fullydescribed hereinafter, and then pointed out in the claims.

'tion of part of the improvement.

Reference is to be had to the accompanying drawings, forming a part of this specification, in which similarletters of reference indicate corresponding parts in all thefigures.

Figure 1 is a side elevation of the improvement. Fig. 2 is an enlarged sectional eleva- Fig. 3 is an inverted sectional plan view of part of the frame, the revoluble disk, and gear-wheels. Fig. 4 is an inverted plan view, with parts in section, of the crank-arm and ratchet-wheel; and Fig. 5 is a sectional plan view of part of the improvement on the line a", 00 of Fig. 2.

The improved ratchet-drill brace is provided with a U-shaped frame A, formed at one end with a handle B and atits other end with a hollow casing or disk 0, closed on the under side by a suitable cover 0. From the handle B projects a bearing B, engaging one end of the U-shaped crank-arm D, arranged to turn within the U-shaped frame B, as can be readily seen by reference to Fig. 1. The other end of the crank-arm D is formed with an enlargement D, loosely engaging a pin E, arranged in line with the bearing B and forming a bearing for the enlarged end of the crank-arm D. The pin E projects from a disk F, mounted to revolve in the casingO and carrying on the pin E a ratchet-wheel G, adapted to be engaged by either of two pawls H or H, pivoted on the enlargement D of the crankarm D. The pawls H and H are pressed on by a coiled spring H so as to hold the free ends of the pawls in engagement with the teeth of the ratchet-Wheel G. In order to throw either of the pawls H or H out of mesh with the ratchet-wheel G, a leverIis provided, pivoted on the enlargement D andformed at. its ends with projections or lugs I and I adapted to engage corresponding notches H and II, respectively, in the pawls H and H, respectively. When the leverIis'turned into the position illustrated in Fig. 4, the projection I engages the notch H in the pawl H, so that the free end of the said pawl II is'held out of mesh with the ratchet-wheel G and only the pawl H isin mesh with the said ratchet-wheel. Thus when the crank-arm D is turned. a rotary motion is given to the said the ratchet-wheel G at a point opposite the previous engagement of the pawl H. When the operator now turns thecrank-arm D in an opposite'direction, the disk F is given a movement which is the reverse .of the movement it had at the timethe pawl H was in engagement with the ratchet wheel G. The pawls H and H, as well as the lever I, are preferably arranged on the under side of the enlargement D, thelever I projecting slightly at its ends from the sides of the said enlargement, so as to be under control of the operator.

In the disk F is jonrnaled a series of gearwheels J, in mesh at their inner sides with a central gear-wheel K, secured on a shaftL, mounted to turn in suitable bearings formed in the hub F of the disk F. The lower end of the shaft L carries the chuck N of an improved construction for supporting the drill transmitted tothe central gear-wheel K, so that the shaft L, carrying the chuck and drilling-t-ool, is revolved at'a very high rate of speed. As shown in the drawings, the proportion is such that one revolution of the crank-arm D gives four revolutions to the shaft L and the chuck N. The latter is preferably constructed in the manner illustrated in Fig. 2, the lower end of the shaft L being provided for this purpose with an enlarged screw-threaded end 0, formed with recesses O, and on which screws and slides a casing P, formed with a partial thread P, engaging the recesses and engaging with its lower end the beveled ends of the gripping-jaws Q and Q, adapted to engage and support the drilltool. The shanks of the gripping-jaws Q and Q are formed with lugs Q extending past each other in opposite directions and supported on a pin R, forming the pivot for the jaws and held transversely in a fork O of the threaded end 0, in which work the shanks of the jaws Q and Q, which are free to swing open or shut. The casing Pis formed on the inside with an annular flange P adapted to engage the shoulders Q formed on the jaws Q and Q, to prevent the casing from dropping olf the threaded end when the partial thread P engages the recesses O. A springS is held on the pin R and presses with its free end .on

the shanks of the jaws Qand Q, so as to open 7 the latter, the closing being accomplished by the casing engaging the wedge-shaped ends of the jaws Q and Q. It is understood that by sliding the casing P well up into the slot 1 of the threaded part 0 and by giving it a quarter-turn .it will close the jaws and rigidly secure the bit ortool.

It will be seen that a ratchet-drill brace constructed in this manner is very simple, can

be readily taken apart to be examined, and permits of reversing the motion of the drilltool. It will further be seen that the speed can be increased or diminished, as the case may be, by changing the relative proportions of the gear-wheels described.

In using the ratchet-drill brace the handle B on the frame A is veryconvenient for holding the latter in proper position while operating the crank-arm D.

Having thus described my invention, I claim as new and desire to secure by Letters Patent-- 1. In a ratchet-drill brace, the combination,

a ratchet-wheel adapted to be alternately engaged by the said pawls, a disk mounted to turn within the said casing and carrying the said ratchet-wheel, a series of gear-wheels journaled in the said disk and in mesh with the internal gear-wheel of the said casing, a shaft journaled in the said disk and carrying a gear-wheel in mesh with the said series of gear-wheels, and a lever pivoted on the said crank-arm and formed with lugs adapted to alternately engage notches in the said springpressed pawls, substantially as shown and described.

3. In a ratchet-drill brace, a chuck comprising a revoluble shaft formed with a forked end, a screw-tn read and recesses therein,a casing fitted to slide and to screw on the said thread and recesses, jaws held in the forked end of the said shaft and adapted to be closed by the said casing, the said casing being provided'with an annular flange adapted to engage shoulders on the said jaws, and a spring for opening the said jaws, substantially as shown and described.

WILLIAM P. NOLAN. Witnesses:

J. JiIoNAMARA, W. W. BLAKE. 

